Device for regaining components of knocked-out mold and core sand and pieces

ABSTRACT

A device for regaining components of knocked-out mold and core sand pieces, in which said knocked-out pieces are crushed in a container and conveyed through perforations to a separator for filtering out the dust component from the crushed material and feeding the remainder into a storage container.

United States Patent Inventor Appl. No.

Filed Patented Assignee Priority Konrad Grob Goldach, Kenton St. Gall, Switzerland 785,630

Dec. 20, 1968 Jan. 5, 197 1 Alfred Gutmann Gesellschaft fur Maschinenbau Hamburg, Germany Dec. 21 1967 Germany DEVICE FOR REGAINING COMPONENTS OF KNOCKED-OUT MOLD AND CORE SAND PIECES 5 Claims, 3 Drawing Figs.

[51] Int. Cl B02c 13/14 [50] Field ofSearch 241/41, 50, 55, 56, 73

[56] References Cited UNITED STATES PATENTS 1,977,771 10/1934 McMahan 241/56X 2,945,633 7/1960 Lykken et al. 241/41 Primary Examiner-Travis S. McGehee Attorney-Walter Becker ABSTRACT: A device for regaining components of knocked out mold and core sand pieces, in which said knocked-out pieces are crushed in a container and conveyed through perforations to a separator for filtering out the dust component from the crushed material and feeding the remainder into a storage container.

PATENTEDJAN 1911 3,552,662

INVENTOR.

DEVICE FOR REGAINING CQMPONENTS F moggzo-our MOLD AND CORE SAN'D PIECES The present invention concerns a device for recovering the components of knocked-out mold and core sand pieces. More specifically, the present invention relates to the recovery of the components of mold and core sand pieces which are obtained in foundries after the pouring has been completed.

It is an object of the present invention to treat such pieces, also called lumps or chips, in such a way that primarily quartz granules will be maintained and can be used again as sand.

It is another object of this invention so to treat said lumps or chips that the binding substance, such as furan and other suitable resins and cement, contained in said lumps or chips will be recovered in active condition.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawing, in which:

FIG. I illustrates partially in section and partially in side view a device according to the present invention.

FIG. 2 is a top view of FIG. 1.

FIG. 3 shows a detail of the left-hand portion of FIG. 1 as seen in the direction'of the arrow III of FIG. 1.

The device according to the present invention is characterized primarily in that at the bottom" of a housing which receives the broken off lumps and chips there are provided rotating beater vanes while in at least a portion of the housing walls there are provided outlet openings for the mass which has been crushed by the beater vanes. Furthermore, outside said outlet openings there is provided a container for collecting the crushed mass which last mentioned container is followed b a de ice for separating'the sand granules from the crushed mass.

The broken off lumps and chips which are fed into the housing, preferably from the top, are crushedby means of blades or vanes rotating at a high speed and are centrifuged by said blades against the housing wall. The housing wall is provided with outlet openings in the form of almesh, which openings have a size corresponding to the granular size of the respective quartz sand. Similarly, the size of the openings in the perforated or screen surface which may extend over the entire circumference of the housing wall is selected in conformity with the granular size of the quartz sand. By means of the size of the said outlet openings, it is possible to determine the time during which the mass remains in the housing, and the quantity of granules passed through said outlet openings may be brought into agreement with the speed of rotation of the blades so that the total mass will be crushed to quartz granules of the original size without crushing any material quantity of the granules.

In order also to recover the binding substance in active condition (as far as it has not been'burned during the pouring operation), which binding substance is during the crushing operation obtained in a fine and even upto dustlike condition, it is suggested in accordance with the present invention, to create an additional air flow by means of a blower which is arranged below the crusher blades and comprises blades rotating with said crusher blades while the bottom of the housing is provided with a suction opening. This air flow conveys the finely diminuted or dustlike binding substance to and through the outlet openings of the housing wall while simultaneously aiding the discharge of the form sand granules and while additionally dynamically closing the housing at the bottom thereof.

For purposes of improving the recovery of the useful components, a centrifugal separator is connected to the collecting container of the crushing device, preferably through the intervention of a suction funnel. This centrifugal separator separates the quartz granules from the crushed mass and furthermore separates from the dustlike components the active binding substance while conveying the separated quartz granules to a supply container and-conveying the active binding substance to a filter. The separated quartz granules and the still active binding substance can be used again in the form of sand or core sand whereas the dust and burned binding substance is collected in the filter in the form of dust and waste.

Referring now to the drawing in detail, the device for crushing the broken-off or knocked-out lumps or chips I is shown in the portion A of FIGS. 1 and 2. This device comprises a round housing 2 which tapers in upward direction but may also be cylindrical and is closed by a cover 3 which is hinged to the housing and has an inlet opening 4 for the lumps and chips. The bottom 5 of the housing has an opening 6 through which extends the shaft 8 of an electric motor 7. Closely above the bottom 5, the device is provided with a two-arm beater 9 the ends 10 and 11 of which are bentslightly downwardly and upwardly respectively'(see also FIG.-3). At the bottom side, the blades of the beater 9 are on a disc 12 provided with vanes 13 so that these members together with the bottom 5 form a blower. A portion 14 of the wall of the housing 2 is provided with perforations 15 communicating with a collecting container 16. The container 16 leads into an adjustable suction funnel 17 from which a suction conduit 18 leads to a centrifugal separator l9having connected thereto a container 20 and a filter 21. The blades 9 which rotate at a high speed crush the lumps and chips 1 until they have reached a granular size which corresponds to the granules of the quartz sand and centrifuge the quartz granules through the openings I5 into the collecting container 16. The bent blade ends 10, II will crush the lumps or chips which might get stuck in the dead corners I of the bottom of the housing.

The dustlike up to finest granular mass which is obtained during the crushing operation and which still contains active binding substance is conveyed through the perforations 15 into the container 16. This is effected additionally by the air flow which is produced by the blades. 13 while exerting a suction effect through the openings 6. This air flow also closes the housing 2 at the bottom 5 thereof. In view of the suction effect exertedby the centrifugal separator 19, the mass conveyed to the container 16 is drawn into the separator 19 through the funnel 17. The separator 19 separates the mass on one hand into quartz granules and active binder substance which are collected in the container 20 for reuse, and on the other hand into dust and burned binder components which in the filter 21 are separated from the conveying air and are collected in the container 22.

The width of the outlet openings 15 of the housing 2 is selected in conformity with the hardness and the size of the obtained chips or lumps and in conformity with the quartz granules selected for the form or core sand. The size and shape of the housing 2 and of the blades 9 as well as the speed of said blades and the circumference of the mantle section 14 of housing 2 which contains the outlet openings 15 may be selected in conformity with the desired output of the device. For relieving the centrifugal separator 19, the suction pipe 18 may be replaced by a conveying means, for instance, an additional blower, a bucket conveyor, or the like.

It is, of course, to be understood that the present invention is, by no means, limited to the particular showing in the drawing but also comprises modifications within the scope of the appended claims.

Iclaim:

l. A device for regaining components of knocked-out mold and core sand pieces, which includes: housing means having an inlet and bottom and also having a housing wall portion provided with perforations, rotatable-beater means arranged within said housing means adjacent said bottom for crushing knocked-out mold and core sand pieces fed into said housing means through said inlet, and for centrifuging granules and particles corresponding in size to the size of said perforations through the latter, collecting vessel means communicating with said perforations for collecting the crushed material passed from the inside of said housing means through said perforations, and separator means adapted to withdraw crushed material from said collecting vessel means 'and to separate sand granules from said withdrawn crushed material.

2. A device according to claim l ,in which beater means include beater blades with upwardly and said vessel means and to convey said dustlike component from the crushed material received from said vessel means and to convey said dustlike component to said filters while conveying the remainder to said container means.

5. A device according to claim 1', which includes suction funnel means interposed between said vessel means and said separator means. 

1. A device for regaining components of knocked-out mold and core sand pieces, which includes: housing means having an inlet and bottom and also having a housing wall portion provided with perforations, rotatable beater means arranged within said housing means adjacent said bottom for crushing knocked-out mold and core sand pieces fed into said housing means through said inlet, and for centrifuging granules and particles corresponding in size to the size of said perforations through the latter, collecting vessel means communicating with said perforations for collecting the crushed material passed from the inside of said housing means through said perforations, and separator means adapted to withdraw crushed material from said collecting vessel means and to separate sand granules from said withdrawn crushed material.
 2. A device according to claim 1, in which beater means include beater blades with upwardly and downwardly bent outer end portions.
 3. A device according to claim 1, in which said housing bottom is provided with an air inlet opening, and in which the bottom side of said beater blades is provided with vanes operable to draw air through said air inlet opening into said housing and to direct said drawn-in air toward said perforations.
 4. A device according to claim 1, which includes container means, and filter means, and in which said separator means is formed by a centrifugal separator operable to separate the dustlike component from the crushed material received from said vessel means and to convey said dustlike component from the crushed material received from said vessel means and to convey said dustlike component to said filters while conveying the remainder to said container means.
 5. A device according to claim 1, which includes suction funnel means interposed between said vessel means and said separator means. 